Molecular compounds consist of:
- a atoms of nonmetals bonded together by covalent bonds
- b ions held together by electrostatic forces
- c metal atoms in a crystalline network that share electrons among many atoms
- d both b and c
The correct answer is a, since molecular compounds are formed when nonmetal atoms share electrons through covalent bonds. This creates discrete molecules rather than larger ionic or metallic structures. While options b and c describe different types of bonding (ionic and metallic), they do not pertain to molecular compounds, which exclusively involve nonmetals and covalent bonds. Understanding the distinction between these types of bonds is crucial for classifying various compounds accurately.